BARYMETRIC FORMULAS APPLICABLE TO CHICKENS OF THE LOCAL BREED (GALLUS GALLUS) ON THE EAST COAST OF MADAGASCAR

Résumé

Abstract

A better morphological knowledge of the local chicken will influence how to improve breeding techniques. Production is based on the carcass yield of the animal. This is mainly the direct result of the weight of the live chicken. This live weight is the only parameter used in estimating the commercial value of local chicken. The objective of this study is to develop and validate barymetric equations for estimating live weight in local chickens reared on the east coast of Madagascar. An equation for predicting the live weight of local chicken breeds based on measurement variables is designed using a linear regression method: PV = a + b1LC+ b2TP + b3LCou + b4ENV + b5LT + b6DT + b7HCr + b8LCr + b9HB. The variables are classified and then entered into the model equation according to their level of correlation with the variable to be explained. For the live weight prediction equation, the best barymetric formula is the one formed by 4 variables where PV = -1503.25*LC - 60.16*ENV + 76.76*TP+ 107.29*Lcou (n=902; R² =0.785; R²aj= 0.784; ETR=366.18; CV=16%; p<0.0001). The reliability of the barymetric equation in this study is confirmed. The accuracy of the live weight of local chickens is essential to enable better valorisation of the sector, especially economically. The results demonstrate that barymetric formulas provide a reliable tool for estimating live weight in local chicken breeds and can be effectively used in field conditions where weighing scales are unavailable.

Keywords : Modelling, barymetric, local poultry, eastern coast of Madagascar